/*
 *  Copyright (c) 2001 Sun Microsystems, Inc.  All rights
 *  reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *  notice, this list of conditions and the following disclaimer.
 *
 *  2. Redistributions in binary form must reproduce the above copyright
 *  notice, this list of conditions and the following discalimer in
 *  the documentation and/or other materials provided with the
 *  distribution.
 *
 *  3. The end-user documentation included with the redistribution,
 *  if any, must include the following acknowledgment:
 *  "This product includes software developed by the
 *  Sun Microsystems, Inc. for Project JXTA."
 *  Alternately, this acknowledgment may appear in the software itself,
 *  if and wherever such third-party acknowledgments normally appear.
 *
 *  4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA"
 *  must not be used to endorse or promote products derived from this
 *  software without prior written permission. For written
 *  permission, please contact Project JXTA at http://www.jxta.org.
 *
 *  5. Products derived from this software may not be called "JXTA",
 *  nor may "JXTA" appear in their name, without prior written
 *  permission of Sun.
 *
 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *  DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 *  ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 *  USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 *  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 *  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 *  OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 *  SUCH DAMAGE.
 *  ====================================================================
 *
 *  This software consists of voluntary contributions made by many
 *  individuals on behalf of Project JXTA.  For more
 *  information on Project JXTA, please see
 *  <http://www.jxta.org/>.
 *
 *  This license is based on the BSD license adopted by the Apache Foundation.
 *
 *  $Id: AbstractDialogManager.java,v 1.3 2007/05/28 22:00:51 nano Exp $
 */

package net.jxta.myjxta.dialog;

import net.jxta.peergroup.PeerGroup;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

/**
 * @author james todd [gonzo at jxta dot org]
 * @version $Id: AbstractDialogManager.java,v 1.3 2007/05/28 22:00:51 nano Exp $
 */

abstract class AbstractDialogManager
        extends DialogManager {

    /**
     * The list of registered DialogPipeListeners
     */
    private HashMap<PeerGroup, ArrayList<DialogPipeListener>> listeners = null;

    public AbstractDialogManager(String name, String type) {
        super(name, type);
    }

    /**
     * Initialize this DialogManager to work in the indicated
     * PeerGroup
     *
     * @param pg the PeerGroup for which to initialize the DialogManager
     */
    public abstract void initialize(PeerGroup pg);

    /**
     * { @inheritDoc }
     */
    public abstract void close();

    /**
     * Add a new DialogPipeListener
     *
     * @param pg       the PeerGroup in which the DialogPipeListener operates
     * @param listener the DialogPipeListener to add
     */
    public synchronized void addPipeListener(PeerGroup pg,
                                             DialogPipeListener listener) {
        List<DialogPipeListener> list = getListeners(pg);
        boolean isEmpty = list == null || list.size() == 0;

        // add the listener keyed as belonging to the indicated
        // PeerGroup to the list of listeners
        addListener(pg, listener);

        // If there where no listeners for this PeerGroup before
        // initialize the DialogManager for this PeerGroup
        if (isEmpty) {
            initialize(pg);
        }
    }

    /**
     * Removes a DialogPipeListener previously registered for
     * the indicated PeerGroup
     *
     * @param pg       the PeerGroup to which the DialogPipeListener belongs
     * @param listener the listener to remove
     */
    public void removePipeListener(PeerGroup pg, DialogPipeListener listener) {
        if (this.listeners != null &&
                this.listeners.containsKey(pg)) {
            this.listeners.get(pg).remove(listener);
        }

        // If the list of listeners is now empty, shut it down.
        close();
    }

    public void clearPipeListeners(PeerGroup pg) {
        if (this.listeners != null &&
                this.listeners.containsKey(pg)) {
            this.listeners.remove(pg);
        }

        close();
    }

    protected String getName() {
        return super.getName();
    }

    protected String getType() {
        return super.getType();
    }

    /**
     * Return the list of registered DialogPipeListener for the
     * indicated PeerGroup
     *
     * @param pg the PeerGroup for which to retrieve the
     *           registered DialogPipeListener
     * @return the list of registered DialogPipeListener for the
     *         indicated PeerGroup
     */
    protected ArrayList<DialogPipeListener> getListeners(PeerGroup pg) {
        if (this.listeners == null)
            return null;
        return this.listeners.get(pg);

    }

    /**
     * Adds a new DialogPipeListener for the indicated PeerGroup
     *
     * @param pg       the PeerGroup for which to add the DialogPipeListener
     * @param listener the listener to add
     */
    protected void addListener(PeerGroup pg, DialogPipeListener listener) {
        // if the HashMap does not exist create it and
        // if it does not contain an element for pg, create the element
        if (this.listeners == null ||
                !this.listeners.containsKey(pg)) {
            if (this.listeners == null) {
                this.listeners = new HashMap<PeerGroup, ArrayList<DialogPipeListener>>();
            }

            this.listeners.put(pg, new ArrayList<DialogPipeListener>());
        }

        // and add the listener to the HashMap if necessary
        ArrayList<DialogPipeListener> list = this.listeners.get(pg);

        if (!list.contains(listener)) {
            list.add(listener);
        }
    }
}
